Light-sensitive polymers for photography



United States Patent LIGHT-SENSITIV E POLYMERS FOR PHOTOGRAPHY Donald A. Smith, Albert c. Smith, Jr., and Cornelius c. Unruh, Rochester, N. Y., assignors to Eastman Kodak fompany, Rochester, N.'Y., a corporation of New ersey No Drawing. Application June 11, 1954, Serial No. 436,251

6 Claims. (Cl. 260-63) This invention relates to light-sensitive copolymers containing recurring units having the probable general structure I CH-OHOONHR OH in which R represents one of the groups Particular features of our invention reside in copolymers containing recurring units having the probable general structures Patented Oct. 29, 1957 extent to which the polymer has been insolubilized in 7 Organic solvents in which the polymer was originally soluble. The light-sensitive polymers find particular use in photomechanical processes for the preparation of resist images. In this usage a supported layer of the polymer is exposed to a subject such as a line, halftone or continuoustone image to render the polymer insoluble in the region of exposure following which the unexposed portion of the polymer-layer is removed from the support by treatment with a suitable solvent. The resulting element comprising an insoluble polymeric relief image on the support is then utilized, for example, as a lithographic printing plate if the image has been prepared on a hydrophilic support such as grained zinc, surface-hydrolyzed cellulose ester, casein, etc. If the insoluble polymeric image has thus been prepared on a metal support such as zinc or copper plates, the usual etching solutions may be applied to obtain a relief printing plate.

The following examples illustrate the preparation of the polymers of the invention containing recurring units as indicated.

Example 1 OOH so it A solution of 2.0 g. of a styrene-maleic anhydride copolymer (121) in 20 ml. of dry pyridine was treated with 2.0 g. of ethyl 4-aminocinnamate in 10 ml; of pyridine. The solution was then heated 20 hours on the steam bath, cooled, and the product precipitated in dilute acetic acid. The fibrous precipitate was squeezed dry, dissolved in 20 ml. of acetone and precipitated in water, The purification was repeated once more yielding 3.5 g. of dried polymer. v

Found: N=3.3%. Calculated: N=3.56 V Exposure of a coating of this polymer through a photo.- graphic halftone negative using a source of ultraviolet light followed by development with methyl ethyl ketone yielded an insoluble polymeric relief imageon the support.

Example 2 0011 t omen-o0 Two grams of the styrene-maleic anhydride copolymer was dissolved in 10 ml. of dry pyridine. To the solution was added a slurry of 4.5 g. of m-aminobenzalacetophenone (prepared according to Annalen, 441, p. 247) in 15 ml. of dry pyridine. The mixture was heated on the steam bath for 4 hours, diluted with an equal volume of acetone, and poured into a large excess of agitated dilute hydrochloric acid. The bright yellow precipitate was redissolved in a mixture of acetone and dioxane and again poured into distilled water containing .a little hydrochloric acid. The polymer Was reprecipitated a third time from dioxane solution into distilled water, washed well with distilled water, and dried at 40 C. Four grams of a friable yellow polymer were obtained which contained 3 4 to give a relief image which corresponded to the image to light described in Example 3 and readily gave an image on the negative. of the insolubilized polymer.

Example 5 I /COOC2H5 GHr-OHCHGHGONHOOH=GHCH=G\ JJOOH OOOCsHs Example 3 A solution of 5.8 g. of diethyl p-aminocinnamalmald nate in 5 ml. of dry pyridine was added to a solution of CHg-CHCH(JH-OONHG-GO-GEHJHO 4.0 g. of the styrene-maleic anhydride copolymer dis- (JJOOH solved in 35 ml. of dry pyridine. This was heated on the steam bath for 1 hour, and the product was poured into an excess of agitated dilute acetic acid to give a red,

gummy precipitate which was washed several times with Y dilute acetic acid. The product was dissolved in 70 ml.

To a Solution of 10 8- 0f the styfene-malelc anhydl'lde of acetone, filtered, and reprecipitated into dilute hydrocopolymef in 90 y Py Was added 11 of chloric acid. The fibrous precipitate was wellwashed amino chalcone (p p according to the procedure with distilled water and dried. The yield was 5.5 g. prodgiven in the Journal Of thfi Chemical Y,' 9 P- uct which had a nitrogen content of 1.6%, denoting 36 1419). This solution was heated on the steam bath for ol percent reaction,

4 hours. The solution was cooled, diluted with an equal This product coated from methyl ethyl ketone, ex-

volume of acetone, and then poured into an agitated soluposed to ultraviolet light through a photographic negative tion of 200 cc. of concentrated hydrochloric acid in 3 l. and then developed in methyl ethyl ketone gave an inof distilled water. A yellow-brown fibrous product was 4 soluble image.

. a V I Example 6 -cH,- 'oH-fcH- m-oONH-O-GflflllQQ-Mhdh-O-Qon. $00K obtained which was then thoroughly washed with distilled Two and nine-tenths grams of the styrene-maleic anwater and dried at 40 C. The polymer was redissolved hydride resin was dissolved in cc. of dry pyridine at in dioxane and reprecipitated into distilled water, leached 40 steam bath temperature. To this was added 1.0 g. (0.25

in distilled water, and dried at 40 C. The yield was mole equiv.) of p-aminoberlzalanisalacetone, and heating 17 g. The analysis was found to be: C=74.3, H=5.4, was continued.

N=3.3. Calculated: C=76.2, H=5.4, N=3.3. After 4 hours the material was removed from the A coating of this polymer was made on a surface-by steam bath and diluted with cc. of dioxane. The

drolyzed cellulose acetate sheet and exposed through a 45 solution was poured slowly into a highly agitated mixture photographic negative to ultraviolet light. The exposed of 1.5 liters of water and 25 cc. of concentrated hydrocoating was developed in methyl ethyl ketone, and there chloric acid. A fine, orange-yellow precipitate was prowas obtained an image of insolubilized polymer correduced. This was isolated by filtration and air dried. sponding to that of the negative. The product was dissolved in 75 cc. of dioxane and Example 4 Y O-TH; CHr-CH-CH( .HGONHC COCH=CH-O0 no reprecipitated in 1.5 liters distilled water. After air drying the yield was 2.8 g.

Fifteen grams of the styrene-maleic anhydride copoly- N, Pjclundi N, mer was dissolved in 135 ml. of dry pyridine. To this A sample Q? "P Polymer sublected t0 the above test was add d 20 f piperonal p aminoacetophenone for hght sensitivity when coated on a hydrolyzed cellupared as described in Berichte, 37, p. 393 and the mixlose acetate had gr of liwmparsd a Speed ture heated on the steam bath for 4 hours. The redof 2 for the llght-sensltlve P y polyvmylcmnamat brown solution was cooled and pored into 3 liters of under the same mndlfifmsdistilled water containing 250 ml. of concentrated hydrochloric acid. The reddish-brown fibrous precipitate was washed well with distilled water and dried. The product I was redissolved in' acetone and filtered. The filtrate CH OH ZH CH CONH was poured into agitated distilled water and the brown, 0011 L fibrous polymer was washed thoroughly in distilled water,

Example 7 and dried at 40 C. The yield was 25 g.

This material was subjected to the test for sensitivity To 6.73 g. (0.033 mol) of the styrene-maleic anhydride resin dissolved in 50 ml. of hot, dry pyridine was added a solution of 5.63 g. (0.033 mol) of S-aminoacenaphthene in 25 ml. of dry pyridine. sulted.

The solution was refluxed for 1% hours and then poured slowly into 1000 ml. of distilled water containing 100 ml. of acetic acid. The resulting tan, fibrous precipitate was washed in a mixture of 1000 m1. of distilled water and 100 ml. of acetic acid, then in three successive 1000 ml. distilled water washes. Thepro'duct was air dried.

The dry product was dissolved in 200 ml. of dioxane and reprecipitated in water. It was again air dried.

Analysis.-Calcd for C24H21O3N: C, 78.1; H, 5.2; N, 3.8. Found: C, 76.9; H, 5.5; N, 3.7

The polymer was found to be light-sensitive when tested according to the methods of the above examples.

Example 8 O OOH COCH:

To a solution of 1.84 grams of a vinyl-acetate-maleic anhydride copolymer in 20 ml. of dry pyridine was added 2.5 grams of 3-aminobenzalacetophenone. The mixture was heated on the steam bath for two hours, then 2 ml. of water were added and the mixture heated a further /2 hour. The solution was then poured into a large volume of dilute hydrochloric acid, and the yellow-green fibrous polymer was thoroughly washed with distilled water, then dried at 40 C. The product weighed 3.6 grams and contained 4.3% nitrogen.

The polymer was coated on a surface-hydrolyzed cellulose acetate base from moist dioxane solution, and the coating was exposed to a source of ultra-violet light through a photographic half-tone negative. The exposed coating was developed in dioxane (containing a little water) and a positive image corresponding to the negative was visible on the surface.

Similar light-sensitive polymers are obtainable by reaction of the aromatic amines of the above examples with other copolymers of maleic anhydride such as with vinyl acetate, isopropenyl acetate, vinyl alkyl ethers, as vinyl ethyl ether, ethylene, acrylic and methacrylic acid esters and by reaction of the amines with polymers containing acyl halide groups such as homopolymers and copolymers of acrylyl or methacrylyl chloride or fumaryl chloride.

What we claim is:

1. A resinous copolymer containing recurring units of A dark solution re-' the ccsa'sishng oi acetate and styrene 2nd recurring units having the general structure:

-cn-rr eanas 5 ooH wherein R represents a substituent of the cla'ss consisting of m on=on-oooo.m

/C 0 0 (hm Ocn=cn-on=o c o 0 can. Ocn=on-o o-cn=cn- 3 o on. and

ing the structure:

0 O OH CH=CH-C O 3. A resinous polymer containing recurring units having the structure:

COOH

4. A resinous polymer containing recurring units having the structure:

OOH

5. A resinous polymer containing recurring units having the structure:

COOCzHa COOH COOCnHs 6. A resinous polymer containing recurring units having the structure: 7

COOH

References Cited in the file of this patent UNITED STATES PATENTS 1,965,710 Murray July 10, 1934 2,566,302 Allen Sept. 4, 1951 FOREIGN PATENTS 479,838 Great Britain Feb. 11, 1938 

1. A RESINOUS COPOLYMER CONTAINING RECURRING UNITS OF THE CLASS CONSISTING OF VINYL ACETATE AND STYRENE UNITS, AND RECURRING UNITS HAVING THE GENERAL STRUCTURE: 